Apertures for corrugated fiberboard containers



R. L. CAIN Nov. 26, 1968 APER'IURES FOR CORRUGATED FIBERBOARD CONTAINERS Filed Jan. 25, 1967 FIG.3

INVENTOR. ROBERT L.CAIN.

BY W

ATTORNEY United States Patent 3,412,919 APERTURES FOR CORRUGATED FIBERBOARD CONTAINERS Robert L. Cain, West Lafayette, Ind., assignor to Inland Container Corporation, Indianapolis, Ind., a corporation of Indiana Filed Jan. 25, 1967, Ser. No. 611,740 4 Claims. (Cl. 229-7) ABSTRACT OF THE DISCLOSURE A corrugated fiberboard carton for fluids having at least an inner liner coated to protect the liner from degradation from fluids, and having an aperture for filling or pouring provided with an annular grommet protecting the raw edges of the fiberboard at the aperture from the contained fluids, the grommet rigidifying the carton and adapted to receive a plug, valve, or pour spout.

This invention relates to corrugated fiberboard containers for packaging or containing fluids or powders; and more particularly to fluid tight or leak-free apertures in such containers.

Reference is made to co-pending United States Patent 3,341,104, Loheed et al., filed Apr. 20, 1965, and to the corrugated fiber-board container for fluids described therein. The liquid tight apertures of this invention will be shown to be particularly useful when properly installed in appropriate locations of the liquid tight container described in Loheed et al., 3,341,104.

Apertures in corrugated fiberboard packaging are well known to the art. Depending on their size, configuration, location and purpose, they are variously named slots, drain holes, ventilation holes, handholes (for carrying purposes) and the like. Such conventional apertures are mere cutaway holes which leave raw or unprotected paperboard fibers of which the containerboard structure is composed exposed to the atmosphere. To make paperboard packaging serviceable for containing, shipping, dispensing, and pouring liquid and fluid products and powders, grommets are afiixed in the apertures. Such grommets, when properly swaged or seated-in-place provide a liquid-tight seal of the periphery of the aperture, thus preventing liquid from soaking into otherwise unprotected paperboard fiber, causing its degradation, and rendering the entire package worthless.

The novel use of such grommets in apertures of corrugated fiberboard and other similar packaging materials, as in the present invention, is done with the object of providing an inexpensive liquid-tight universal mounting base for assorted molded fitments, formed plugs, tubing, stoppers and the like. Such universal mounting base has important utility when used in conjunction with fluid tight containers as in Loheed et al., 3,341,104.

A further application or object of this invention is seen in the protection of an air-vent aperture in such package to allow free discharge of the contained product with full protection for the containerboard structure of the package.

Still another application for the grommeted apertures of this invention is demonstrated by the sealing off of paperboard fibers at exposed marginal areas of drain holes and the like in packages designed for wet service shipment; such as in the iced-pack poultry service, hydrocooling of produce, and similar wet service exposed package applications.

Still another application or objective for the use of grommets to form liquid tight junctions between two separate or diiferent types of materials may be seen in the joining of a molded fitment and dispensing tube to plastic film. Here the grommet is secured into the plastic film 3,412,919 Patented Nov. 26, 1968 and serves as a junction or mounting base for desired fitments. The fitments can be fitted into and held securely within the interior margin of the seated grommet.

Suitable grommets may be constructed from any appropriate high modulus of bending material such as metallic sheet stock; including stainless steel, brass, aluminum, tin plate, and the like. Grommets fashioned or molded from plastic materials may also be utilized. The lesser expensive materials, particularly tin plate, are preferred. Metal sheet in the 0.010 to 0.015 inch thickness range is preferred; but this invention is not limited to the thickness range mentioned. It has been found that the mechanical swaging or seating-in-place operation of this invention to produce positive leak freeness around apertures in packaging materials can be accomplished more rapidly than similar joinings accomplished by heat-seal techniques or methods now employed to join thermoplastic materials for generally similar purposes. By reason of this more rapid grommet swaging operation, it is found that leak freeness around apertures is also realized at lower expense than by the aforementioned heat seal methods; in which a definite heat-pressure-cooling cycle is required. In addition, the dimensional stability of metallic and other high modulus materials provides a highly reliable opening for pressure tight fitments. To accomplish the sealing-off of apertures utilization of the conventional two-piece grommet and washer assembly or a one-piece grommet provide equal success. The one-piece grommet alone obviously requires less material and is therefore less expensive and is preferred for those reasons.

If the aperture be sealed with a two-piece grommet, preferable orientation of the grommet is such that the washer part be external to the contained liquid, and that the whole assembly be swaged in securely with appropriate tooling to prevent leaks.

When the one-piece grommet (grommet alone) is used, it is preferable that the flange of the grommet be placed external to the contained liquid, with the rolled or swaged end of the grommet being internal. In such orientation, the one piece grommet interior rolls or flows tightly around the packaging material at the aperture; binding it securely and providing freedom from leaks.

A further advantage of such application of the 0ne piece grommet is found in that any uncoated edge of the grommet material internal to the package is securely tucked deep around the crimped packaging material; thus making it unnecessary to treat uncoated base metal edges by reason of their being "removed-from-exposure as a result of seating the grommet.

This rolling-under action of seating the grommet makes it practical to use commercial tin plate for the grommets; since only the original coated surfaces of the tin plate are left exposed to packaged commodity.

The above and other novel features of the invention will appear more fully hereinafter from the following detailed description when taken in conjunction with the accompanying drawings. It is expressly understood that the drawings are employed for purposes of illustration only and are not designed as a definition of the limits of the invention, reference being had for this purpose to the appended claims.

In the drawings, wherein like reference characters indicate like parts:

FIGURE 1 is a perspective view of a container provided with an aperture;

FIGURE 2 is a sectional view of a two piece grommet employed in connection with the aperture;

FIGURE 3 is a sectional view of the aperture with the two piece grommet installed and provided with a plug;

FIGURE 4 is a sectional view of a one piece grommet, and

3 FIGURE 5 is a sectional view of the grommet of FIG- URE 4 installed in a container aperture. I

Referring to FIGURE 1, there is shown a container 20 for liquids, or other highly fluid materials, in which a fill or dispensing aperture 22 is provided. Such aperture may be for filling, pouring, dispensing or for receiving a tube. Several such apertures may be provided, and may act as a vent. The aperture comprises a grommet, and may be sealed by a plug 24. The grommet forming the aperture may comprise two parts as illustrated in FIGURE 2, or a single part as in FIGURE 4.

The grommet of FIGURE 2 comprises a member having a tubular shank 26, and an outwardly flared flange 28, and a separate washer like member 29 having a central aperture 30, adapted to fit over the shank 26. In FIGURE 3, the grommet is shown positioned to protect the circular aperture 31 cut in the container cover 32. It will be seen that the shank 26 has been outwardly formed over the inner portion of the washer member 29, as at 34, and the liners 36 and 38 and intervening corrugating medium 40 are squeezed together along annular lines 42 and 44 of inside and outside surfaces of the liner 38 and 36. In this manner, the raw annular edges 46, 47 and 48 of the liners and corrugating medium cut to form the aperture are protected from the liquid in the container. By applying a barrier coating 39 to the inside suriace of the liner 38, the fibers of which the container is constructed are kept dry, and protected from damage that would otherwise occur, were the aperture left unprotected. In this manner, a container capable of being used for liquids is prevented from being rendered worthless by the contained liquid. By the employment of a barrier coating and protecting the aperture in the manner described, the container though filled with liquid, will retain its maximum strength. Any suitable fitting can be inserted into the shank aperture, such as a plastic cork or plug 24 as illustrated.

In the form shown in FIGURES 4 and 5, the grommet shank 60 is inserted into the aperture 62 cut in the corrugated fiber board 64, and thereafter the shank is rolled outwardly, upwardly and inwardly, as indicated in FIGURE 5, the annular roll up 66 and flange 61 squeezing the liners 70 and 72 and corrugating media 76 adjacent the edge of the apertures. By employing a barrier coating on the inside surface 78 of the liner 72, the roll up flange 66 will provide a water tight annular seal. If the grommet be tin plated on one side as at 80, the roll up will protect the unplated surface 82, and the raw edge 84 from liquid. Thus there is presented nothing but a barrier coated surface, and a tinned surface 80 to the liquid contents of such a container, so that the container, when filled with liquid is completely protected from loss due to wetting of the fibers of which the fiberboard is constructed.

While alternate forms of the invention have been illustrated and described, it is to be understood that the invention is not limited thereto. As various changes in the construction and arrangement maybe made without departing from the spirit of the invention, as will be apparent to those skilled in the art, reference will be had to the appended claims for a definition of the limits of the invention.

What is claimed is:

1. A container formed of corrugated fiberboard having a barrier coating on the inside walls thereof, said container fiberboard having an aperture therein, grommet means having a tubular shank extending through the aperture and having spaced outwardly flaring flanges extending over the contiguous inner and outer surfaces of the fiberboard adjacent said aperture, and said flanges being deformed and compression the fiberboard therebetween, the internal flange of said grommet means and shank being integral and engaging the internal barrier coated surface of the fiberboard surrounding said aperture along a continuous unbroken line whereby to protect the fiberboard aperture from exposure to liquids within the container, or passing through the grommet shank.

2. A container as set forth in claim 1 wherein the grommet means comprises an external preformed flange, and the internal flange is externally flared and annularly rolled toward the other flange and inwardly beyond the line toward the shank, whereby the edge of said rolled flange is entirely disposed inwardly of the line of contact of the rolled flange with the internal surface of the fiberboard.

3. A container as set forth in claim 2 wherein the internal wall of the shank and the internally exposed surface of the rolled flange are tin plated.

4. A container according to claim 1 wherein the grommet means comprises a member comprising a tubular shank and a flared internal flange integral therewith, and the external flange comprises an annular element closely fitting over the shank, and in which the shank is outwardly formed annularly over the inner edge portion of the annular element to compress the fiberboard and engage the internal flange against the internal barrier coating along an uninterrupted continuous line, surrounding the aperture.

References Cited UNITED STATES PATENTS 1,481,217 1/1924- Maloy 285203 XR 1,588,847 6/1926 McGee -8 2,266,611 12/1941 Martin et al. 285-205 2,347,686 5/1944 Hothersall 229-7 2,562,005 7/1951 Wenzel et al. 24141 XR 2,801,948 8/ 1957 Walker.

2,901,800 9/1959 Koehl 24-141 2,973,119 2/1961 Parker 229-7 XR 3,152,711 10/1964 Mumford et al. 215-40 XR DONALD F. NORTON, Primary Examiner. 

